用《WHY数学表达式可视化工具》绘制3D图形？
1、先画一个贝壳：
vertices = dimension1:160 dimension2:160
u = from 0 to (6*PI) dimension1
v = from 0 to (2*PI) dimension2
k = 1.2
a = 1.5
w = (k^u) * (1+cos(v))
x = w*cos(u)
y = w*sin(u)
z = (k^u)*sin(v) - (k^u)*a
2、用鼠标的滚轮可以放缩图片。
3、用鼠标的右键可以全方位观察图形；
具体怎么的控制方法，需要自己体验。
4、查看贝壳的绘制过程。
5、再换个模样的贝壳：
vertices = dimension1:1000 dimension2:72
u = from 0 to (20*PI) dimension1
v = from 0 to (2*PI) dimension2
m = -0.09
k = 3
a = 1
b = 1
e = pow(E, m*u)
w = (a + b*cos(v))*e
x = w*cos(u)
z = w*sin(u)
y = (k*a + b*sin(v))*e
6、加入随机数的贝壳，每解析一次，都会得到不一样的图形。
vertices = dimension1:1000 dimension2:72
u = from 0 to (32*PI) dimension1
v = from 0 to (2*PI) dimension2
m = -1/(rand_int2(2, 100))
k = rand2(1, 100)
a = 1
b = rand2(0.5, 2)
e = pow(E, m*u)
w = (a + b*cos(v))*e
x = w*cos(u)
z = w*sin(u)
y = (k*a + b*sin(v))*e
7、蚌壳的模样：
vertices = dimension1:36 dimension2:72
a = from 0 to (1*PI) dimension1
b = from (-PI*0.5) to (PI*0.5) dimension2
r = 10.0
x = r*cos(b)*sin(a)
y = r*sin(b)*sqrt(a)
z = r*cos(b)*cos(a)
u = a
v = b*2
